Smoky skies and unhealthy air conditions are expected to linger over Tracy through the week as smoke from the Creek Fire burning in Fresno and Madera counties and other wildfires throughout the state filters into the San Joaquin Valley.
On Tuesday the San Joaquin Valley Air Pollution Control District reissued a health caution for residents until the fires are extinguished.
The health caution originally went up on Aug. 17 after a lightning ignited a series of wildfires around the valley.
On Wednesday Tracy residents woke to orange skies a fine layer of ash across cars and outdoor furniture as the smoke settled over the city.
The Creek Fire began on Friday and has quickly exploded to 163,138 acres with 0% containment as of Wednesday morning.
Shifting winds on Tuesday and Wednesday are expected to push smoke directly into the San Joaquin Valley bringing increased particulate matter pollution -- called PM 2.5 made of smoke, dust, soot and ash that are 2.5 micrometers or smaller -- along with the potential for high levels of ozone.
The winds are also expected to gust bring dust and elevated of particulate matter, 10 microns and smaller called PM10, through the valley.
The air district warned that microscopic particles in the smoke can trigger asthma, aggravate chronic bronchitis, and increase the risk of heart attack and stroke. Young children, older adults, and anyone with existing respiratory conditions, including COVID-19, are especially at risk from this type of air pollution.
Anyone who can smell smoke or see falling ash should consider the air unhealthy and should move indoors to a filtered, air-conditioned environment and keep windows closed.
The air district emphasized that cloth and paper masks used to reduce the transmission of COVID-19 via respiratory droplets are not sufficient to filter out the microscopic particles that make up smoke.
Current air quality conditions can be monitored through the air pollution districts Real-time Air Advisory Network at www.myraan.com.
Information about wildfires affecting the valley can be found at www.valleyair.org/wildfires.
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